Goldschmidt 2025 Conference

Chemical and isotopic variations among extra-terrestrial materials and Solar System bodies reflect diverse chemical and physical processes that occurred at different evolutional stages of the Solar System. The composition of the Earth, a rocky planet with oceans and life, was shaped through a series of processes, such as accretion of dust to its protoplanetary building blocks, the formation and differentiation of magma oceans, the final Moon-forming giant impact, and the delivery of volatiles. 

The compositions of Solar System materials thus provide a window into the 4.57-billion-year history of the Solar System and even the evolution of the Galaxy. Understanding the compositional diversities of Solar System bodies also provides insights into the compositions of exoplanets, for which observational constraints are steadily increasing.

This theme focuses on the chemical and isotopic compositions of extra-terrestrial materials, planets, satellites, and small bodies of the Solar System, and aims to understand the evolutionary processes that shaped planet compositions over the history of the Galaxy. We welcome contributions from diverse fields – sample return missions, robotic explorations, astrophysical modeling, astronomical observations across various wavelengths of light, laboratory experiments and analyses, and sample curation. We anticipate new ‘chemistry’ between disciplines to propel the field forward!

The interior of the Earth comprises most of our planet, and shapes its long-term evolution and present-day surface conditions. By integrating the finds from various fields of study, such as geochemistry, geodynamics, geophysics, petrology, and mineral physics—be it through experiments, observations, or theories—we gain profound insights into the inner workings of our planet and its dynamic interaction with the surface across space and time. In this theme, we encourage disciplinary and interdisciplinary session proposals on the chemical and physical processes occurring in the Earth’s interior across all scales of time and space, the nature of material and energy exchange between the interior and surface, insights into deep reservoirs including the upper mantle, transition zone, lower mantle, outer and inner core, as well as interactions between the crust, mantle and core and their evolution over time.

The lithosphere represents the archive of Earth’s differentiation and it records interactions between the mantle, the crust, the atmosphere and the hydrosphere. In this theme, we invite contributions that address the present state of the lithosphere, as well as its formation and evolution through time. In particular, we encourage sessions that bring new insights into (1) the processes and timescales of continental and oceanic crust formation, (2) the processes controlling deformation, metamorphism and its secular variations, (3) the geodynamics of mantle–crust differentiation and the onset of plate tectonics, (4) the growth of the continental crust and its effect on the evolution of other geochemical reservoir(s), (5) the timing and rates of melting at the base of the lithosphere, (6) the origin of mantle heterogeneities, (7) the interactions between internal (crust and mantle) and external (atmosphere and hydrosphere) reservoirs, and their impact on the biosphere and (8) the use of early Earth’s history as a proxy for planetary evolution and exoplanet exploration. We encourage specialised and multidisciplinary contribution sessions that address these topics through the investigation of natural samples, geochemistry, petrology, geophysics, experiments and modeling.

Throughout Earth history volcanism, magmatic systems, and their associated hazards have significantly impacted the planet, from building and jeopardizing its habitability to the disruption of human infrastructure.  An integrated understanding of magmatic events and hazards benefits from a combined approach integrating geochemical, petrological, geochronological, seismological, and tectonic methodologies, built on solid field observations of geological relationships; such understanding may also include studies of extra-terrestrial bodies. We encourage session proposals that explore the breadth of volcanic and plutonic magmatic systems, and the hazards they pose, using the wide range of tools available to us - including theoretical, experimental, and analytical approaches. The expected contributions to the proposed sessions will emphasize temporal and spatial variability across the geological timescale, from field studies and samples, to analogue models, and numerical experiments, and where appropriate, how these bear on the hazards society faces today.

Achieving the United Nations Sustainable Development Goals, and climate provisions of legislation that call for significant increases in renewable energy infrastructure, will require extraction of resources including a variety of minerals and geologic hydrogen, together with carbon capture and storage (CCS), at an unprecedented scale and speed. The urgency to diminish CO₂ emissions and to find and produce minerals will be enormous. We must appreciate that mineral and hydrogen production, as well as nuclear energy and CCS have the potential to adversely affect the environment and communities. This means that the minerals and energy sectors face greater challenges than ever before. The sessions within this theme will therefore focus on all aspects of mineral resources, energy transition, and CCS including: (1) the formation of mineral and energy resources and the use of this knowledge for responsible resource exploration and extraction; (2) new and less invasive approaches for the exploration and extraction of raw materials; (3) the generation and storage of low-carbon energy resources such as geothermal, green hydrogen, and  nuclear energy; (4) carbon capture from concentrated sources or the atmosphere and storage in-situ and ex-situ in nonreactive and reactive rocks; (5) innovative approaches to geometallurgy, mineral processing, and the recycling of end-products containing metals and minerals to develop circular economies; (6) the effective management, mitigation and use of waste products such as radioactive waste, plastics, process water and mine tailings; and (7) securing supplies of industrially important, critical, and strategic metals, industrial minerals, and gases that are subject to global or regional supply disruption. We welcome session proposals that cover all aspects of these topics, including field studies (terrestrial, marine, planetary), petrological and geochemical characterization, mineralogical and metallurgical investigations, as well as experimental, thermodynamic and modeling approaches to resource geochemistry and geology.

Analytical and computational techniques supply the data and interpretative frameworks that allow exploration of complex natural systems. Advances in such techniques, including the improvement of existing geochemical tools, new applications, and technological innovations are crucial to developing the geoscience toolbox necessary to answer questions over a range of time and size scales and to predict geochemical and geophysical processes and future impacts. We welcome sessions that highlight research at the frontiers of geochemically-oriented analytical and computational approaches, including both fundamental and applied research. Session proposals should focus on method development, application, and scientific outcomes across all sub-disciplines of Earth and planetary sciences. These can include – but are not limited to – elemental and isotopic characterization of natural systems in terrestrial and extraterrestrial environments, physico-chemical investigations of in situ processes and laboratory experiments, and numerical simulations from the atomic to the mesoscale. Studies detailing advancements in integrating data resources, data processing, and approaches to scaling-up observations are also welcome.

This theme invites sessions that explore the co-evolution of life, the environment and the planet on geological timescales. Within this theme, we aim to include sessions on the emergence and evolution of metabolisms and biogeochemical cycles, the influences of biological, geological, astronomical and chemical processes on Earth’s long-term habitability and key developmental milestones such as Earth’s surface oxidation, global glaciations and radiation or extinction events. We welcome sessions that span a wide range of disciplinary perspectives and methodological approaches, from numerical simulations to field-based studies of ancient environments and modern analogues.

This theme focuses on the interactions between Earth surface processes, sedimentary and geochemical fluxes, and biogeochemical cycles. Solicited topics include weathering processes within the Earth’s Critical Zone and across the land-ocean interface, and their links with global elemental cycling and climate across a range of spatial and temporal scales, including anthropogenic impacts. We encourage sessions covering topics such as geomorphological evolution, links between physical, chemical and biogeochemical weathering processes, elemental and isotopic fluxes, and enhanced silicate weathering. We also welcome topics that investigate the connections between these processes within the Earth system, and their impact on past, present and future climate. Contributions to the Theme can be based on modern observations from individual sites or from comparative studies, process-based experiments, sedimentological proxy records of surface and/or deeper Earth processes, as well as modelling frameworks.

A combination of biotic and abiotic processes shapes the cycling of various elements in the geosphere, biosphere, cryosphere, hydrosphere, and atmosphere. In return, these biogeochemical cycles have dramatically impacted the functioning of the biosphere and its evolution over geological time, in particular through redox cycling of nutrients and contaminants, production and consumption of greenhouse gases, and turnover of organic and inorganic substrates in ancient and modern environments. Element cycling in many cases is controlled by the availability of oxidized and reduced compounds that function as electron acceptors and donors or enzyme cofactors. Traces of these biogeochemical interactions can be found as specific mineralogical, isotope or trace element patterns and organic or inorganic biomarkers including specific genes, microbial communities or other remnants of biological activity. Deciphering how to find such traces of biological activity is key for the search of past or modern life on Earth or other planets. This theme invites sessions that will address such biogeochemical interactions, with a focus on terrestrial and marine ecosystems and the impact of these interactions on both modern and ancient elemental cycles including relevant aspects for climate and the environment (water, soil, sediment and atmosphere) and the history of life. Also invited are sessions that discuss new and environmentally relevant metabolisms, coupled elemental cycles, biogenic-mediated redox and mineralization reactions. We encourage sessions including interdisciplinary approaches in geomicrobiology, biogeochemistry and astrobiology including laboratory and field investigations, cultivation experiments, isotope analyses, spectroscopic and microscopic techniques and molecular “omics” studies.

The geochemical processes that drive the transfer and transformation of elements across the biosphere, hydrosphere, lithosphere, and anthroposphere result from the complex interplay of biotic and abiotic reactions. While these reactions occur across interfaces (e.g., air-water, water-particle, and particle-particle) and over small spatial distances, they are drivers of large-scale phenomena. For instance, the geochemical cycling of carbon, nutrients, and metals at air-water-particle interfaces in response to environmental perturbations (e.g., warming, extreme hydrologic events such as droughts and floods, resource extraction, among others) dictates ecosystem health, soil function, and water quality. Understanding of such cross-scale interactions is urgently needed to cope with the challenges of global change.

This theme will host sessions that address the geochemical cycling of major and trace elements in terrestrial and freshwater ecosystems. In particular, the theme will bring together sessions that address system complexity, especially in response to global change and anthropogenic perturbation, through the use of experimental, computational, and field-based investigations. We encourage submissions of sessions on 1) mechanisms and rates of coupled processes at environmental interfaces (e.g., redox and mineral (trans)formation reactions, plant uptake, organic matter cycling, and geochemistry at surface water-groundwater interfaces); 2) geochemical studies conducted across relevant biogeochemical gradients; 3) in-situ approaches including isotope studies, chemical imaging, and geophysical measurements; 3) advanced analytical methods including advanced spectroscopic approaches and multimodal approaches at small and large scales; and 4) climate-induced perturbations of geochemical cycles (e.g., thawing permafrost, wildfire, soil warming, water level fluctuations, increased frequency and intensity of storms, and sea level rise).

The field of Environmental Geochemistry and Human Health explores natural and anthropogenic geochemical processes that affect environmental contamination, nutrient availability, and human health outcomes. Broadly, topics include how the movement and transformation of chemical elements in the environment affect the quality of air, water, and soil, and consequently, human health. By studying these interactions with human biological systems on various scales (from cells to communities), this theme aims to understand how geochemical factors influence public health, encompassing both fundamental and applied studies. Fundamental research may include understanding elemental cycles, concentration variations, isotopes, and element speciation across all environmental spheres. Applied research may focus on the impact of elemental cycles on human activities on elemental cycles. We welcome contributions from all related fields. Key research areas include, but are not limited to, developing chemical speciation methods, evaluating water-mineral interface effects, creating stable/radioisotope tracers, studying biological influences on geochemical cycles, and modelling these cycles. Applied research covers environmental issues, climate change, and their health impacts, such as contaminant behavior (e.g., heavy metals, pesticides, radionuclides) in water, soil, and air; toxic substance removal, useful element recovery; nutrient bioavailability, and health effects of exposure to metals, metalloids and organic pollutants. By integrating geochemical data with health studies, this theme aims to develop strategies for managing environmental risks, promoting better health through improved environmental quality, and contributing to effective interventions and policies.

The ocean and atmosphere have been key to the habitability of our planet since life originated. However, in the current Anthropocene, the key processes and equilibria that underpin the functioning of these dynamic systems are coming under ever increasing pressure, with potentially very severe consequences for our climate. This theme will focus on all geochemical and biogeochemical research activities that concern processes within the ocean and the atmosphere, as well as the interaction between these environmental spheres and the land surface.

This theme invites sessions that can cover a wide range of topics, including (but not limited to): the cycling of major and trace elements, or other chemical species, in the oceans and atmosphere; the sources, sinks, and dynamics of greenhouse gasses and pollutants; development and application of proxies to study environmental change and Earth system evolution; and, sensitivity of global biogeochemical cycles to natural and anthropogenic perturbations, now and through time.

We welcome sessions that utilize observational, experimental and modeling approaches, or combinations thereof. This can include field-based measurements (including autonomous observing platforms) or experiments, laboratory-based experiments, remote sensing, proxy development, numerical simulations and data assimilation techniques.

Climate variations occur on many spatial and temporal scales, with a variety of impacts on surface environments and biotas. This theme aims to provide insights into the operation, magnitude, and rates of past climatic and environmental change, with a view to better understanding the past and to inform projections for the future. We welcome contributions using both geological and modern records that capture variations in atmospheric, oceanic, and cryospheric processes, alongside those which address important climate feedbacks and mechanisms, especially the role of the carbon cycle. Sessions may choose to focus on transient events in the geological past, discrete periods of time and/or sets of mechanisms and processes. We anticipate offering sessions that focus on the application of marine, terrestrial, and ice core proxies; geochemical dating tools; Earth system and geochemical modeling, and model-data comparisons; as well as the development of new proxies and models to constrain the climate of the past, present, and future.

The geosciences offer unique solutions to global and local challenges, including many of the Sustainable Development Goals. However, translating this promise into practice necessitates an open, diverse, equitable and inclusive scientific model. This cross-cutting theme links sessions and abstracts, submitted to this theme or to any of the other themes, that explore various aspects of using geochemistry to inform the public and policy. Efforts to diversify the field of geochemistry and create an inclusive community are also welcome. Examples of topics linked to this theme include: the role of geochemistry in providing solutions for society in large or smaller communities; effective engagements with policy-makers; educational strategies to promote geochemical understanding in schools, during outreach and beyond; advancing equitable and inclusive participation in science; developing open data and software infrastructure; and developing a new scientific culture that supports accessible and diverse science for the future. We hope that by sharing our experiences and materials across all the themes in geochemistry, we will better integrate and highlight these very important efforts across the entire community through this cross-cutting theme.